Alignment of surfaces is a perennial problem in a variety of fields, ranging from construction to interior decorating. Alignment is necessary for walls that should be perpendicular to a floor, or otherwise plumb. Masonry and brick-laying practitioners are well aware of the importance of plumbed and aligned surfaces and chalk lines. A home interior decorated with pictures and other wall ornamentation makes a much better appearance when the ornamentation is aligned, especially with respect to vertical or horizontal alignment. Many mechanical and electrical alignment devices are available, and some laser devices are available. However, some of these products are cumbersome, and others are not suitable for certain uses. Chalk lines, for instance, are sometimes undesirable for use in finished, interior areas.
One aspect of alignment-product performance, and in particular of laser-alignment products, that could be improved is the width, brightness and straightness of the laser light. A visible, straight laser line is acceptable, but may be limited in its brightness over a distance, and may also tend to defocus and become dimmer as a user works further away from the source of the laser. Rotating lasers are used to project lines on walls perpendicular to the direction of propagation of the laser. As a result, such devices may have limited utility or may not work in confined spaces requiring a longer alignment tool.
Moreover, a conventional laser is not well-equipped for projecting a flat or planar beam of light. The essence of laser light is that it is coherent or substantially monochromatic, that is, of a single wavelength or of a narrow band of wavelengths. Thus, when a beam of laser light is refracted through a prism, the prism output does not result in a spreading of the beam as with ordinary “white” light, but rather results in a coherent, focused beam, very similar to the input. The laser beam is thin and is visible in a useful manner only when projected onto a surface.
Another aspect of laser alignment products that could be improved is the inability of laser devices to work around obstructions. That is, if a wall-hanging, such as a picture frame, interrupts the laser beam, it may be blocked from further projection. In this case, it is necessary to mark locations or heights, one by one, rather than working with the actual objects, in order to align them. Obstructions may include moldings placed in a doorway, picture frames in the way of those being aligned on one horizontal line, the operator of the device, other obstacles, or even textured or stuccoed surfaces on interior walls.
While there are devices that direct a laser beam parallel to but away from a surface requiring alignment, these devices require the use of a marker device or detector component to sight the beam and mark corresponding locations on the wall adjacent the beam. Use of such a device requires multiple components and at least two people, one to align the laser and another to mark the wall. Moreover, the wall itself requires marking with this method.
Another aspect of laser alignment products that could be improved is the inability of laser alignment devices to rotate or pivot relative the wall or object on which the laser light is intended to operate. With such limitations, a user must mark a first laser line, move the laser alignment devices angularly relative to the first mark, and then project and mark a second laser line. As a result of having to move laser alignment device and mark the laser line several times, inaccuracies in the measurements may occur, the wall may more easily become damaged, and unnecessary time is wasted.
A conventional laser beam projector is thus not able to project a laser line on the wall on which it is mounted, nor can it go around obstructions. A laser alignment beam mounted on the wall where alignment is needed would allow a person seeking alignment, whether a carpenter, a painter, or an interior decorator, to accomplish his or her task in a quicker and easier fashion. The ability to work around obstacles would save much time and effort. Such laser alignment devices must be aligned themselves, and are typically equipped with a tripod and a sophisticated leveling device so that they read true for horizontal and vertical plumbs. While leveling is necessary, such sophistication as a tripod adds to the expense and bulkiness of the leveling device. What is desired is a convenient, easy-to-level laser device useful for aligning objects. It would be even more desirable if the alignment device could be easily mounted on a vertical or horizontal surface, and oriented in the desired direction. Better alignment devices are thus required to overcome these deficiencies in the prior art.